Heritable differences in respiratory drive and breathing pattern in mice during anaesthesia and emergence†  H. Groeben, S. Meier, C.G. Tankersley, W. Mitzner, R.H. Brown  British Journal of Anaesthesia  Volume 91, Issue 4, Pages 541-545 (October 2003) DOI: 10.1093/bja/aeg222 Copyright © 2003 British Journal of Anaesthesia Terms and Conditions

Fig 1 (a) Respiratory rate and (b) pressure amplitude (Amp), as a measure of tidal volume, of 10 C57BL/6J (B6), 11 C3H/HeJ (C3), and 10 C3B6F1/J (F1) male mice measured at baseline; during 0.5, 1.0, and 1.5 MAC isoflurane anaesthesia; and during recovery from anaesthesia at 5, 10, 20, and 30 min (RI–RIV). Data points are mean (sd). British Journal of Anaesthesia 2003 91, 541-545DOI: (10.1093/bja/aeg222) Copyright © 2003 British Journal of Anaesthesia Terms and Conditions

Fig 2 (a) Increase in respiratory rate (RR) and (b) Amp, as a measure of tidal volume, of 10 C57BL/6J (B6), 11 C3H/HeJ (C3), and 10 C3B6F1/J (F1) male mice measured at baseline; during 0.5, 1.0, and 1.5 MAC isoflurane anaesthesia; and during recovery from anaesthesia at 30 min (RI–RIV) in response to a challenge with carbon dioxide 8% (mean (sd)). Compared with baseline, the increase in RR in response to hypercapnia was completely blocked at 1.0 and 1.5 MAC for all three strains (P<0.0001), while Amp increases slightly, but not significantly, at 1.0 MAC, and was finally completely blocked at 1.5 MAC (B6 P=0.0068; C3 P=0.0003; and F1 P=0.0043, compared with baseline). At the end of the recovery period, the B6 mice increased their RR significantly compared with the response at 1.0 (P<0.0001) and 1.5 MAC (P<0.0001), and with the response of the C3 mice (P<0.0001) and the F1 progeny (P=0.0110) mice. Furthermore, only B6 mice showed a significant increase in Amp to the carbon dioxide challenge (P=0.0016), while the response of C3 and F1 mice remained attenuated. British Journal of Anaesthesia 2003 91, 541-545DOI: (10.1093/bja/aeg222) Copyright © 2003 British Journal of Anaesthesia Terms and Conditions